Allows us to finally remove the old `serai-dex/substrate` repository _and_
should have CI pass without issue on `develop` again.
The changes made here should be trivial and maintain all prior
behavior/functionality. The most notable are to `chain_spec.rs`, in order to
still use a SCALE-encoded `GenesisConfig` (avoiding `serde_json`).
* move economic security into it's own pallet
* fix deny
* Update Cargo.toml, .github for the new crates
* Remove unused import
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Co-authored-by: Luke Parker <lukeparker5132@gmail.com>